Fibrous base felt containing cellulosic fibers, 10% to 50% asbestos fibers, and 1% to 5% of water soluble cationic polyacrylic resin as a drainage aid

ABSTRACT

A fibrous base felt which includes cellulosic fibers, 10 percent to 50 percent asbestos fibers, and 1 percent to 5 percent of water soluble cationic polyacrylic resin is produced by separately forming a cellulosic fibrous slurry and an asbestos fibrous slurry, adding the polyacrylic resin to the asbestos fibrous slurry, mixing the slurries, and thereafter forming and drying the produced felt. Binders may be employed to saturate the felt subsequent to drying.

United States Patent 1191 Winters [4 1- Apr. 3, 1973 [54] FIBROUS BASE FELT CONTAINING CELLULOSIC FIBERS, TO ASBESTOS FIBERS, AND 1% TO 5% OF WATER SOLUBLE CATIONIC POLYACRYLIC RESIN AS A DRAINAGE AID [7 51 Inventor: Donald C. Winters, Plainfield, NJ.

[73] Assignee: Congoleum Industries, Inc., Kearny,

[22] Filed: Apr. 8, 1970 [21] App1.No.: 26,805

[52] US. Cl. ..l62/145,162/155, 162/168, 162/183 [51] Int. Cl. ..D21h 5/18, D21h 3/38 [58] Field of Search ..162/l45,155,152, 164,168, 162/183; 161/205 [56] References Cited UNITED STATES PATENTS 3,562,097 2/1971 Hazmburg ..162/ X 2,868,641 1/1959 Feigley; ..l62/l55 3,480,847 11/1969 Sewell 61 al... ....162/145 x 3,554,860 1 1971 Lacroix 162/145 3,270,846 9/1966 Al'ledtel' et al. .162/145 x 3,441,474 4/1969 I'IlltCI'lIllS et al. ..162/

Primary ExaminerS. Leon Bashore Assistant ExaminerRichard H. Tushin Att0rney-Richard T. Laughlin and Shlesinger, Arkwright & Garvey 57 ABSTRACT 3 Claims, No Drawings FIBROUS BASE FELT CONTAINING CELLULOSIC FIBERS, 10% TO 50% ASBESTOS FIBERS, AND 1% TO 5% OF WATER SOLUBLE CATIONIC POLYACRYLIC RESIN AS A DRAINAGE AID This invention relates to an improved fibrous base felt, and more particularly to an improved fibrous base felt including both asbestos and cellulosic fibers.

In recent years, resinous surface coverings, and particularly, vinyl surface coverings have been increasingly common and popular in both residential and commercial buildings. The versatility of this type of surface covering has lended itself to both sheet material and tile-like surface coverings. In the manufacture of surface coverings of this type, a resinous wear-like layer is formed on or laminated to a fibrous substrate, and a cushion layer may be interposed between the wear layer and the fibrous layer.

The fibrous support layer usually consists of either a cellulosic fiber felt or a mineral fiber felt, the felt being impregnated with a synthetic resin saturant usually of the synthetic rubber type. One of the problems associated with the prior art cellulosic felts has been to achieve equal dimensional stability in all types of felts, whether they be composed of kraft fibers, rag fibers or the like. Prior art has indicated that the incorporation of l-5 percent of mineral fibers such as asbestos fibers improves the dimensional stability of the cellulose felts. However, when the asbestos fibers were incorporated at levels of -50 percent, the dimensional stability of the felts improved markedly over the prior art teachings.

However, one major problem still existedwhen the asbestos fiber was included at this higher level. The freeness of the stock had to be reduced sufficiently to permit the product to be made on conventional paper machinery.

Accordingly, the primary object of this invention is to produce a fibrous felt including both cellulosic and asbestos fibers which may be produced on conventional paper making machinery.

Still a further object of this invention is to provide a fibrous felt which may be utilized to produce a greatly improved surface covering.

Yet another object of this invention is to produce a fibrous felt from a slurry of cellulosic and asbestos fibers including a polymeric drainage aid.

Still another object of this invention'is to produce a fibrous felt containing both asbestos and cellulosic fibers and having increased freeness in the manufacturing of the felt.

These and other objects and advantages of this invention will become apparent when considered together with the following description and claims.

It has been found that if asbestos fibers are incorporated together with cellulosic fibers such as kraft fibers in'the production of a felt base, the asbestos fibers being present in an amount of about 10 to about 50 percent by weight, the freeness of the stock had to be reduced in order to permit manufacture of the base felt on a conventional paper machine. In order to accomplish the reduction of the freeness to a sufficiently great extent, it has been found that the incorporation of a polymeric drainage aid at a level of about 1 to about 5 percent by dry weight of the fibers into the fibrous slurry provides the necessary freeness in the furnish. In the preferred embodiment, a slurry of the cellulosic fibers is first prepared and is then mixed with a slurry of the asbestos fibers and the polymeric drainage aid. After the slurries are mixed, the fibers are then saturated with the desired binder, which may be of the type well known in the art, such as latex. The presence of about 10 to about 50 percent of asbestos fibers by weight corresponds to about 1 part to about 9 parts of cellulose fiber per part of asbestos fiber.

It has been found that without the incorporation of the polymeric drainage aid into the fibrous slurry, the slurry does not have the freeness required for processing on the conventional paper machinery. The preferred drainage aid used in the practice of this invention is marketed under the trade name Resyn 6002 of the National Starch Company. This resin is a water soluble cationic polyacrylic resin.

Typical non-limiting examples of the fiber slurry and the saturant used therewith are as follows:

EXAMPLE I A slurry of the following formula was prepared, and slurried at 2 percent consistency:

- Water 6837.0 g Linerboard kraft 77.5 g Wood flour 28.0 g White rag felt 34.5 g

550 gm wet cellulose X 2% consistency =l 1.0 gm dry cellulose 175 gm wet asbestos X 2% consistency =3.5 gm dry asbestos Total =l4.5 gm dry fibers i 1 100%= 24.1 asbestos fibers 14.5 g %=75.9Z; cellulose fibers 23.3 gm. Resyn 6002 o 2 725 gm slurry X 100/ 3.2% Resyn 6002 A sheet was then formed from the slurry and dried, and the sheet was then saturated using a saturant having the following formula:

Water 712.0 g Silicone defoamer 0.] g Triton 1.1 g Microcrystalline wax 3.8 g Melamine Resin 154.0 g Catalyst 17.7 g Firestone Latex 106.5 g Blue pigment 4.5 g

After the saturant has completely saturated the sheet, it is dried in the usual manner.

EXAMPLE I] A slurry was formed and slurried at 2 percent con sistency and having the following content:

Water 6860.0 g Pine kraft fiber 93.0 g Wood flour 21.0 g White rag fibers 26.0 g

Five hundred and fifty g of the above mixture was mixed with 175 g of a 2 percent slurry of asbestos fibers in water containing 23.3 g of Resyn 6002. The resultant slurry mixture had the following relative percentages of asbestos and cellulose fibers by weight and the following percentage of drainage aid:

550 gm. wet collulose 2% consistency=1LO gm. dry

While this invention has been described, it will be understood that it is capable of further modification, and

this

application is intended to cover any variations,

used and/or adaptations of the invention following in general, the principle of the invention and including such departures from the present disclosure as come within known or customary practice in the art to which the invention pertains, and as may be applied to the essential features hereinbefore set forth, as fall within the scope of the invention or the limits of the appended claims.

cellulose 175 gm. wet asbostos 2% consistency 3.5 mg. dry asbestos Total=14.5 gm. dry fibers X 100 24.1% asbestos fibers 23.3 gm. Resyn 6002 725 gm. slurry X 100% 75.9% cellulose fibers X100%=3.2% Resyn 6002 After mixing, forming a sheet, and drying the resultant sheet was saturated with a saturant having the following formula:

Water Silicone defoamer Triton Microcrystalline wax UF Resin Melamine Catalyst Firestone latex Blue pigment After the saturant has completely saturated the sheet, they are dried in the usual manner.

In the manner of the two examples, a base felt for resinous surface coverings is formed containing both asbestos fibers and cellulosic fibers. The dimensional stability of the base felt thus formed is markedly increased, and the method of forming the felts may be utilized with standard paper machinery.

What I claim is:

A method of making a fibrous base felt consisting essentially of:

1 and wherein:

said cellulosic fibers include a mixture of kraft and rag fibers. The product produced by the method of claim 1. 

2. A method of making a fibrous base felt as in claim 1 and wherein: a. said cellulosic fibers include a mixture of kraft and rag fibers.
 3. The product produced by the method of claim
 1. 